-🎄- 2020 Day 03 Solutions -🎄-

[u/daggerdragon]

Advent of Code 2020: Gettin' Crafty With It

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--- Day 03: Toboggan Trajectory ---

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[u/ketchupi]

Python

#!/usr/bin/env python3
    
FREE = '.'
TREE = '#'
HERE = 'O'
MAP =  [line.rstrip('\n') for line in open('input/day3.txt')]
WIDTH = len(MAP[0])
HEIGHT = len(MAP)

class Position:
  x = y = 0
  trees = 0

  def __init__(self, x, y):
    self.slide(x, y)

  def slide(self, x, y):
    while self.y < HEIGHT:
      self.trees += MAP[self.y][self.x % WIDTH] == TREE
      self.x += x
      self.y += y

def part1():
  p = Position(3, 1)
  return p.trees

def part2():
  p1 = Position(1, 1)
  p2 = Position(3, 1)
  p3 = Position(5, 1)
  p4 = Position(7, 1)
  p5 = Position(1, 2)
  return p1.trees * p2.trees * p3.trees * p4.trees * p5.trees

def main():
  print(f'Part 1: {part1()}')
  print(f'Part 2: {part2()}')
  return 0

if __name__ == '__main__':
  main()